1. Field of the Invention
This invention relates to automatic washing machines of the vertical axis type and more particularly to a filter system for such automatic washing machines.
2. Description of the Prior Art
U.S. Pat. No. 4,075,876 describes the problem occurring during the agitation and scrubbing of clothing articles in an automatic washing machine when particles of lint are developed from the fabrics being cleaned and become suspended in the laundry liquid. Such lint particles must be removed from the laundry liquid during the washing cycle, otherwise they will be redeposited on the articles being laundered in later steps of the washing program.
It is also known that sediment and debris particles are also removed from clothing articles during the agitation and scrubbing of the clothing articles. Such sediment and debris particles tend to gravitate to the bottom of the washing basket or washing tub.
In one form of automatic washer manufactured and sold by applicants' assignee, the motor in the washing machine is reversed after the agitation cycle and the drain pump is actuated to drain the basket and tub of laundry liquid. At the same time the basket is driven in rotation for the spin cycle or centrifuging mode. Such a cycle sequence is sometimes referred to as a direct-into-spin system because the basket begins its spin cycle before the washing liquid has been drained therefrom.
Such a direct-into-spin system can cause a pressure gradient forcing the laundry liquid from the tub through openings in the bottom of the basket and outwardly through the clothes, thus distributing sediment and debris particles that have settled within the tub on the clean clothes.
U.S. Pat. No. 3,352,130 discloses a filtering arrangement in an automatic washer wherein liquid is pumped from a tub to a closed receptacle or basket by the pumping action of an agitator oscillating within the basket during the washing cycle. Liquid enters the basket from the tub through openings in the bottom of the basket, and liquid circulates from the basket to the tub through perforations in the basket side wall.
Filter elements mounted in the openings in the bottom of the basket collect the lint carried by liquid passing through the openings, and the lint thus collected is thrown off and carried to drain when the basket spins during the centrifuging mode of machine operation. A row of holes is provided in the bottom wall of the basket for permitting sand and other sediment to pass from the basket to the tub. This row of holes formed in the bottom wall of the basket permits unfiltered communication between the basket and the tub. Operating such a structure with a direct-into-spin cycle would allow the deposited sand and sediment particles to reenter the basket area through these holes to be redeposited on the laundered articles.